The channel with periodic ribs is mostly used in design consideration of rotating turbine blade, where coolant flows in the internal cavities. Cooling of the turbine blade is critical to the structural integrity and durability of the turbine. Both internal and external cooling techniques are employed for this. Internal convective cooling takes place along varying cross-sectional area of passage. Apart from the varying passage shapes, turbulent promoters with various shaped and sized ribs, pin fins, etc. are used. The present work focuses on understanding the influence of rib modification of square duct on the turbulence and heat transfer performance by using Dynamic LES (Large-Eddy Simulation) at a Reynolds number based on the average bulk velocity of 20,000. The comparison is made between conventional square (SQ) rib, Backward step (BS) rib, and Forward step (FS) rib with rib height-to-hydraulic diameter ratio of 0.1 and rib pitch-to-rib height ratio of 10. The effect of Coriolis force on the heat transfer performance of the square duct for three rotation numbers Ro= 0.18,0.35 and 0.67 compares with the stationary ribbed duct. The combined influence of Coriolis force and centrifugal buoyancy on turbulent heat transfer also studied by varying the rotation numbers Ro=0.35 and 0.67 and buoyancy parameters Bo=100 and 200.